A large variety of fluid operated pumps, some of which embody axially spaced driving turbine and driven pump impellers, have been described in the prior art, those pumps suitable for bottom hole operation usually requiring somewhat complex mechanical structures. In general, the complexity of these mechanisms is found in the structures utilized to secure the moving pump members within the necessarily limited tubing size, while at the same time finding room for the fluid passageways needed for moving fluid upwardly through or around the pump members. More particularly, the fluid passageways are often so located and of such configuration as to impede, rather than to facilitiate the upward movement of fluid from a production zone.